TREE BIOLOGY - INSIDE
The source material for
these articles are excerpts from various university
research papers, private industry, and web sites
that pertain to the subject matter.
tree problems stem from our poor understanding of how
trees work. We wouldn't plant trees "good and deep,"
if we knew more about tree roots and
how they work. Planting too deep sets up a tree for
severe decay and the death of its root system.
We would know which trees
to remove, and what branches to prune, and how, and if we understood the connections between a tree's
structure its life processes, and its natural defenses. We wouldn't clean out
cavities and fill them with concrete, or coat wounds with "pruning paint".
We wouldn't try to "rejuvenate" a tree by topping it if we
understood that topping is often the first step in the death of the tree;
new sucker growth is not a return to youthful vigor, but a distress signal.
Even learning to identify and call trees by name makes it
easier to choose the right tree for the landscape job you have in mind.
the mid-1970s researchers such as Dr. Alex Shigo have
deepened our understanding of how trees really work. Central to this is
recognizing that trees' defenses are fundamentally different from those of
animals. We and other animals can run from our enemies, or hide, or actually
fight them. But trees
(since they are rooted in place) depend mostly on shedding
weakened parts, and walling off problems that they cannot shed.
of a tree's defensive are passive; but others are active,
triggered by injury and the advance of decay. All of these defenses
have been refined by millions of years of evolution; there are subtle
differences between species, but the general principles are the same all over the
values of trees range from a few dollars for a young ready
for planting to several hundred thousand for an important mature tree on a
historic property. Benefits such as shade, beauty, a place for children to
play, or privacy barriers can be priceless. Yet any tree can be ruined in a
few minutes by ignorant acts, no matter how well intended.
But armed with a clear understanding of how trees work,
anyone can make good tree-management decisions, if he or she will take time for
a little homework.
The basic concepts of tree
biology are not difficult, and once you have them, they are yours for life, since trees provide generous
hints about their problems and their needs. As in most things, the hard part is
taking the time to get started.
Once you understand the basic ideas, it's not hard to
figure out what needs to be done in a particular situation. You may need help doing
it, but you'll know how it should be done. Browse through the topics below,
which make up "Tree Biology"
Anatomy -- The Inner Tree Physiology -- The Living Engine
Defense -- How Trees Survive Practical -- Tree Management
Taxonomy -- The Name Game References --